Enable package-name setting for v5.9+

Support Target Grouping
- Allow opting out of package boundary
- Allow subgrouping within a package
- Default set to package boundary

Fixtures/Miscellaneous/PackageNameFlag/appPkg/Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:999.0
+// swift-tools-version:5.9
 import PackageDescription
 
 let package = Package(

Fixtures/Miscellaneous/PackageNameFlag/fooPkg/Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:999.0
+// swift-tools-version:5.9
 import PackageDescription
 
 let package = Package(

Fixtures/Miscellaneous/TargetGrouping/libPkg/Package.swift

@@ -0,0 +1,19 @@
+// swift-tools-version:5.9
+import PackageDescription
+
+let package = Package(
+    name: "libPkg",
+    products: [
+        .executable(name: "ExampleApp", targets: ["ExampleApp"]),
+        .library(name: "MainLib", targets: ["MainLib"]),
+    ],
+    targets: [
+        .executableTarget(name: "ExampleApp", group: .excluded, dependencies: ["MainLib"]),
+        .target(name: "MainLib", group: .package, dependencies: ["Core"]),
+        .target(name: "Core", group: .package, dependencies: ["DataManager"]),
+        .target(name: "DataManager", group: .named("DataGroup"), dependencies: ["DataModel"]),
+        .target(name: "DataModel", group: .named("DataGroup")),
+        .testTarget(name: "MainLibTests", group: .package, dependencies: ["MainLib"]),
+        .testTarget(name: "BlackBoxTests", group: .excluded, dependencies: ["MainLib"])
+    ]
+)

Fixtures/Miscellaneous/TargetGrouping/libPkg/Sources/Core/Core.swift

@@ -0,0 +1,11 @@
+import DataManager
+
+public struct PublicCore {
+    public let publicVar: Int
+    public init(publicVar: Int) {
+        self.publicVar = publicVar
+    }
+    public func publicCoreFunc() {
+        managePublicFunc()
+    }
+}

Fixtures/Miscellaneous/TargetGrouping/libPkg/Sources/DataManager/File.swift

@@ -0,0 +1,5 @@
+import DataModel
+
+public func managePublicFunc() -> PublicData? {
+    return nil
+}

Fixtures/Miscellaneous/TargetGrouping/libPkg/Sources/DataModel/File.swift

@@ -0,0 +1 @@
+public class PublicData {}

Fixtures/Miscellaneous/TargetGrouping/libPkg/Sources/ExampleApp/main.swift

@@ -0,0 +1,3 @@
+import MainLib
+
+publicFunc()

Fixtures/Miscellaneous/TargetGrouping/libPkg/Sources/MainLib/Lib.swift

@@ -0,0 +1,6 @@
+import Core
+
+public func publicFunc() -> Int {
+    print("public decl")
+    return PublicCore(publicVar: 10).publicVar
+}

Fixtures/Miscellaneous/TargetGrouping/libPkg/Tests/BlackBoxTests/BlackBoxTests.swift

@@ -0,0 +1,9 @@
+import MainLib
+import XCTest
+
+class BlackBoxTests: XCTestCase {
+    func testBlackBox() {
+        let x = publicFunc()
+        XCTAssertTrue(x > 0)
+    }
+}

Fixtures/Miscellaneous/TargetGrouping/libPkg/Tests/MainLibTests/MainLibTests.swift

@@ -0,0 +1,9 @@
+import MainLib
+import XCTest
+
+class TestMainLib: XCTestCase {
+    func testMainLib() {
+        let x = publicFunc()
+        XCTAssertTrue(x > 0)
+    }
+}

Sources/Build/BuildDescription/SwiftTargetBuildDescription.swift

@@ -385,10 +385,21 @@ public final class SwiftTargetBuildDescription {
         try self.fileSystem.writeIfChanged(path: path, bytes: stream.bytes)
     }
 
-    private func packageNameArgumentIfSupported(with pkg: ResolvedPackage) -> [String] {
+    private func packageNameArgumentIfSupported(with pkg: ResolvedPackage, group: Target.Group) -> [String] {
+        let flag = "-package-name"
         if pkg.manifest.usePackageNameFlag,
-           driverSupport.checkToolchainDriverFlags(flags: ["package-name"], toolchain:  self.buildParameters.toolchain, fileSystem: self.fileSystem) {
-              return ["-package-name", pkg.identity.description.spm_mangledToC99ExtendedIdentifier()]
+           driverSupport.checkToolchainDriverFlags(flags: [flag], toolchain:  self.buildParameters.toolchain, fileSystem: self.fileSystem) {
+
+            let pkgID = pkg.identity.description.spm_mangledToC99ExtendedIdentifier()
+            switch group {
+            case .package:
+                return [flag, pkgID]
+            case .excluded:
+                return []
+            case .named(let groupName):
+                let groupID = groupName.spm_mangledToC99ExtendedIdentifier()
+                return [flag, pkgID + "_" + groupID]
+            }
           }
           return []
     }
@@ -513,7 +524,7 @@ public final class SwiftTargetBuildDescription {
             }
         }
 
-        args += self.packageNameArgumentIfSupported(with: self.package)
+        args += self.packageNameArgumentIfSupported(with: self.package, group: self.target.group)
         args += try self.macroArguments()
 
         return args
@@ -527,7 +538,7 @@ public final class SwiftTargetBuildDescription {
 
         result.append("-module-name")
         result.append(self.target.c99name)
-        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package))
+        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package, group: self.target.group))
         if !scanInvocation {
             result.append("-emit-dependencies")
 
@@ -573,7 +584,7 @@ public final class SwiftTargetBuildDescription {
         result.append("-emit-module")
         result.append("-emit-module-path")
         result.append(self.moduleOutputPath.pathString)
-        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package))
+        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package, group: self.target.group))
         result += self.buildParameters.toolchain.extraFlags.swiftCompilerFlags
 
         result.append("-Xfrontend")
@@ -619,7 +630,7 @@ public final class SwiftTargetBuildDescription {
 
         result.append("-module-name")
         result.append(self.target.c99name)
-        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package))
+        result.append(contentsOf: packageNameArgumentIfSupported(with: self.package, group: self.target.group))
         result.append("-incremental")
         result.append("-emit-dependencies")
 

Sources/Build/BuildPlan.swift

@@ -282,6 +282,7 @@ public class BuildPlan: SPMBuildCore.BuildPlan {
 
                 let discoveryTarget = SwiftTarget(
                     name: discoveryTargetName,
+                    group: .package, // test target is allowed access to package decls by default
                     dependencies: testProduct.underlyingProduct.targets.map { .target($0, conditions: []) },
                     testDiscoverySrc: Sources(paths: discoveryPaths, root: discoveryDerivedDir)
                 )
@@ -313,6 +314,7 @@ public class BuildPlan: SPMBuildCore.BuildPlan {
 
                 let entryPointTarget = SwiftTarget(
                     name: testProduct.name,
+                    group: .package, // test target is allowed access to package decls by default
                     type: .library,
                     dependencies: testProduct.underlyingProduct.targets.map { .target($0, conditions: []) } + [.target(discoveryTarget, conditions: [])],
                     testEntryPointSources: entryPointSources
@@ -342,6 +344,7 @@ public class BuildPlan: SPMBuildCore.BuildPlan {
                         // Allow using the explicitly-specified test entry point target, but still perform test discovery and thus declare a dependency on the discovery targets.
                         let entryPointTarget = SwiftTarget(
                             name: entryPointResolvedTarget.underlyingTarget.name,
+                            group: entryPointResolvedTarget.group,
                             dependencies: entryPointResolvedTarget.underlyingTarget.dependencies + [.target(discoveryTargets.target, conditions: [])],
                             testEntryPointSources: entryPointResolvedTarget.underlyingTarget.sources
                         )
@@ -1000,12 +1003,14 @@ private extension PackageModel.SwiftTarget {
     /// Initialize a SwiftTarget representing a test entry point.
     convenience init(
         name: String,
+        group: Group,
         type: PackageModel.Target.Kind? = nil,
         dependencies: [PackageModel.Target.Dependency],
         testEntryPointSources sources: Sources
     ) {
         self.init(
             name: name,
+            group: group,
             type: type ?? .executable,
             path: .root,
             sources: sources,

Sources/CompilerPluginSupport/TargetExtensions.swift

@@ -16,12 +16,14 @@ public extension Target {
     @available(_PackageDescription, introduced: 999.0)
     static func macro(
         name: String,
+        group: TargetGroup,
         dependencies: [Dependency] = [],
         path: String? = nil,
         exclude: [String] = [],
         sources: [String]? = nil
     ) -> Target {
         return Target(name: name,
+                      group: group,
                       dependencies: dependencies,
                       path: path,
                       exclude: exclude,

Sources/PackageDescription/PackageDescriptionSerialization.swift

@@ -166,6 +166,12 @@ enum Serialization {
         case `macro`
     }
 
+    enum TargetGroup: Codable {
+        case package
+        case excluded
+        case named(String)
+    }
+
     enum PluginCapability: Codable {
         case buildTool
         case command(intent: PluginCommandIntent, permissions: [PluginPermission])
@@ -196,6 +202,7 @@ enum Serialization {
 
     struct Target: Codable {
         let name: String
+        let group: TargetGroup
         let path: String?
         let url: String?
         let sources: [String]?

Sources/PackageDescription/PackageDescriptionSerializationConversion.swift

@@ -219,6 +219,16 @@ extension Serialization.TargetType {
     }
 }
 
+extension Serialization.TargetGroup {
+    init(_ type: PackageDescription.Target.TargetGroup) {
+        switch type {
+        case .package: self = .package
+        case .excluded: self = .excluded
+        case .named(let groupName): self = .named(groupName)
+        }
+    }
+}
+
 extension Serialization.PluginCapability {
     init(_ capability: PackageDescription.Target.PluginCapability) {
         switch capability {
@@ -270,6 +280,7 @@ extension Serialization.PluginUsage {
 extension Serialization.Target {
     init(_ target: PackageDescription.Target) {
         self.name = target.name
+        self.group = .init(target.group)
         self.path = target.path
         self.url = target.url
         self.sources = target.sources